The island is too small to support a battle fleet, but it could host the systems that make a maritime approach hazardous: coastal guns, torpedo boats, destroyers, submarines, mine-laying facilities, and observation. Its value would come from disrupting German movement and buying time for the main Royal Navy to arrive. A Heligoland flotilla could perform the Harwich Force's offensive light-force role from Germany's maritime approaches. Reginald Tyrwhitt and Roger Keyes show how aggressive that forward force might become. The Jutland comparison suggests that a released Harwich Force could have threatened the German turn away from the Grand Fleet with torpedoes and immediate contact reports. From Heligoland, that danger would sit directly across Germany's route home.
Notable Point · 36:34-39:13
What a British fortress could support
A British Heligoland would be a compact fortress and light-force base, not an anchorage for capital ships.